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Community Networks and Sustainability: a Surveyof Perceptions, Practices, and Proposed Solutions

Panagiota Micholia∗, Merkouris Karaliopoulos∗, Iordanis Koutsopoulos ∗, Leandro Navarro †,Roger Baig †, Dimitris Boucas‡, Maria Michalis ‡, Panayiotis Antoniadis§

∗ Athens University of Economics and Business , †Universitat Politecnica de Catalunya ,‡University of Westminster, §NetHood Zurich

{panamixo,jordan, mkaralio}@aueb.gr,{leandro, rbaig}@ac.upc.edu,{D.Boucas, M.Michalis}@westminster.ac.uk, panayotis@nethood.org

Index Terms—Community networks, sustainability, incentivemechanisms.

Abstract—Community network (CN) initiatives have been aroundfor roughly two decades, evangelizing a distinctly different paradigmfor building, maintaining, and sharing network infrastructure butalso defending the basic human right to Internet access. Over thistime they have evolved into a mosaic of systems that vary widelywith respect to their network technologies, their offered services, theirorganizational structure, and the way they position themselves in theoverall telecommunications’ ecosystem. Common to all these highlydifferentiated initiatives is the sustainability challenge. We approachsustainability as a broad term with an economical, political, andcultural context. We first review the different perceptions of the term.These vary both across and within the different types of stakeholdersinvolved in CNs and are reflected in their motivation to join suchinitiatives. Then, we study the diverse ways that CN operators pursuethe sustainability goal. Depending on the actual context of the term,these range all the way from mechanisms to fund their activities andsynergistic approaches with commercial service providers, to organi-zational structures and social activities that serve as incentives to maxi-mize the engagement of their members. Finally, we iterate and discusstheoretical concepts of incentive mechanisms that have been proposedin the literature for these networks as well as implemented tools andprocesses designed to set the ground for CN participation. While,theoretical mechanisms leverage game theory, reputation frameworks,and social mechanisms, implemented mechanisms focus on organiza-tional matters, education and services, all aiming to motivate the activeand sustained participation of users and other actors in the CN.

I. INTRODUCTION

A. CNs: history, evolution and current status

Community networks (CNs) are networks inspired, built andmanaged by citizens and non-profit organizations. They arecrowdsourced initiatives where people combine their efforts andresources in a collective manner to instantiate communicationnetwork infrastructures.

While the phenomenon of community initiatives in the field ofmedia is as old as the distinct media themselves, CNs originallysurfaced in the late 90s and have taken many forms and shapes eversince. Typically, these CNs are initiated by tiny groups of people,usually in the range of one to ten, who more often than not are drivenby strong cultural and political motives. They contribute to the fightagainst the digital divide through the provision of telecommunicationservices in under-served areas, the desire for autonomy and self-organization practices, the right to open, neutral networks and

privacy, the experimentation with technology in do-it-yourselfmanner, and the commitment to community ideals and needs.

Whereas some CNs have become obsolete due to the rise of com-mercial high speed broadband networks in the areas CNs operated,others have flourished and evolved into alternative telecommunica-tion network models (section I-B). Not only have they filled in thecoverage gaps of commercial operators providing telecom servicesin rural areas, but they have also developed rich organizationalframeworks with various tools and mechanisms. Typically, theseframeworks emerge as a result of past experiences, successfuland unsuccessful practices and accumulated knowledge. They aremeant to systematize the network’s governance, management andoperation and ensure the CNs sustainability. The establishment offunctional economic models is a key factor to this end.

B. Current motivating factors and new paths for CNs

With a few notable exceptions (e.g., [6]), most communitynetworks have been viewed (and have been viewing themselves)as alternative networks that are incompatible with any commercialnotion, not least because of the strong cultural/political values ofthe small groups that initiated them. Yet, there seem to currentlyexist additional good reasons that motivate a reiteration of theirpositioning in the overall telecommunications landscape and newapproaches to their sustainability.

1) Contributing to broadband connectivity goals: BroadbandInternet access has been promoted as a core priority of politicalagendas throughout the world. In Europe, for example, theEuropean Commission (EC) has set ambitious policy objectivesfor the years to come, summarized under the EC broadband 20201

and 20252 agendas. These agendas demand huge investment costsand grassroots initiatives such as CNs are acknowledged as onepossible response to this challenge and one of four ways to involvepublic authorities in the realization of the broadband vision [19].Community broadband networks such as the Catalan guifi CN [6]are singled out in the EC website as best practices in this respect.

2) Realizing Internet access in developing regions: More thanhalf of the world’s population –specifically women, the poor andmarginalised populations in developing areas– are still offline [24].Many large industrial corporations such as Google, Microsoft and

1https://ec.europa.eu/digital-single-market/en/broadband-strategy-policy2https://ec.europa.eu/digital-single-market/en/broadband-europe

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Fig. 1: Radar charts following CN characteristics i.e., types of services and infrastructure used, number of participating nodes. (a) CNservices. 0: local services as default (Internet connectivity available upon request, manual configuration), 1: mix of local services andInternet connectivity, 2: Internet connectivity as the main service (only management tools as local services), 3: Internet connectivity only.(b) CN Infrastructure. 0: mostly backbone network, access points offered by certain individuals through their home routers, 1: mostlybackbone, good access points, 2: mostly access network (backbone is used to connect to the Internet or interconnect small ”islands”),3: only access network (no backbone network). (c) CN Size. 0: Very small (number of nodes<100), 1: Small (100< number of nodes<1000), 2: Medium (1000< number of nodes <10.000), 3: Large (number of nodes >10.000).

Facebook have stated ambitious objectives for connecting anotherbillion users around the globe. These initiatives are commercial, for-profit and often do not plan access to the open Internet. Combiningthe Do-It-Yourself culture with provisions for unlicensed spectrumand cheap fibre, small crowdfunded community operators thatcreate local value for the local people, without need for complexand centralized systems, may be the obvious way to go aboutrealizing the vision of Internet access to developing regions.

3) Democratization of the telecommunication market: Themarket of telecom services is usually composed of monopoliesand oligopolies that concentrate significant amount of power.The prevention of telecommunications market distortions andthe openness of networks is a key goal set by the InternationalTelecommunication Union (ITU) [33], the EC [19], and theOrganization for Economic Cooperation and Development(OECD) [23]. Monopolies lead to vertically integrated models,where all the layers of the network belong to one entity and end usersare left with limited options when it comes to choosing an operator.

The way they are built and operated makes CNs an idealcandidate model for separating the network infrastructure from theservice provision layer. This separation generates opportunities forsharing the related costs between multiple players and opening thenetwork to public administrations and commercial entities such aslocal/regional ISPs (we elaborate on this model in section II.C).

Our survey does not aim at presenting the status of the hundredsof CN efforts around the globe, nor is it a review of the technologiesused in CNs today. Such information is already available in the CNliterature [62], [37], [27]. Instead, the focus of this survey is on themultiple, often complementary, ways different CN initiatives pursuetheir sustainability. We approach sustainability as a multi-facetedterm, with technical, economic, socio-cultural and political context.We review how these networks fund their activities; which oneshave been the dominant motives behind their initiation and whichones are the aspirations of other actors when participating in them;and what kind of tools and processes are in place as incentives in

the different CNs to best respond to these motives and aspirations.Most of the material for this survey originates from interviews,

both in-person and questionnaire-based, carried out in the contextof the netCommons R&D project [30], [31]. Another big part, onproposed participation incentives and mechanisms, is the result ofan exhaustive review of the existing scientific literature on the topic.Fifteen CNs are primarily discussed in this paper, as listed in TableI-B2. They are selected as good representatives of the diversityin existing CNs with respect to size, supported services (localservices vs. Internet access), network scope/role (backbone networkvs. access network), geographical area of coverage (urban areaswith rich communication alternatives vs.rural under-served areas),organizational structure (involved actors and decision-makingprocesses), and funding sources. The radar chart of Fig. 1 depictshow these fifteen CNs score on the first three attributes (size,services, network role) on a 0-3 scale.

In the remainder of the survey, we first present the layerednetwork infrastructure model, which aims at maximal openness andinvolvement of actors, and explore how CNs fit in it as open accessnetwork instances (section II). Then, in section III, we iterate on theparticipation motives of different actors and their implications forthe CN sustainability. In section IV, we elaborate on the economicsustainability aspects and the funding sources of CNs. Finally,we investigate actual and theoretical practices adopted by CNs orproposed in the literature (section V), before concluding in sectionVI with a list of the most valuable insights out of the survey.

II. NETWORK INFRASTRUCTURES ANDCOMMUNITY NETWORKS

In order to understand how CNs fit in the broader pictureof broadband networks, we contemplate the typical networkinfrastructure layers, the basic actors and the business models –asthey are met in most networks– below.

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CN Location Networkingtechnology Internet Description

AWMN Greece wifi Yes*Built by network technicians, enthusiasts and radio amateurs. Contains native serviceswithout need for public Internet connectivity i.e., games, libraries, network monitoringtools, DNS solutions, and experimental platforms. (2002)

B4RN UK fibre Yes Started by a local volunteer, who led the group as a networking expert. Aimed atbridging the digital divide. Based exclusively on fiber.(2011)

Consume UK wifi YesOne of the first CNs to be conceived and deployed in Europe. The original motivationwas to save Internet access fees for conducting business. It has epitomised theanti-commercial model of networking. Not active anymore. (2000)

FFDN France, Belgium wifi, DSL/fibre Yes An umbrella organization embracing 28 CNs operating across France. Adheres tovalues of collaboration, openness and support of human rights (freedom of expression,privacy). (2011)

Free2Air UK wired, wifi Yes An alternative to the commercial Internet provision. Run by a small number of artistsand a number of other individuals until 2015. (1999)

Freifunk Germany fibre, wifi Yes An open initiative that supports free computer networks in Germany. It attracted manyartists, activists and tech enthusiasts from all over Europe. (2002)

Funkfeuer Austria wireless Yes A free experimental wireless network across Austria, committed to the idea of DIY,built and currently maintained by a group of computer enthusiasts. (2003)

guifi.net Spain fibre, wifi Yes* Started in Osona to serve remote rural areas that were not covered by conventionalISPs. Applies the principles of CPR management. (2004)

i4Free Greece wifi Yes The initiative of a German engineer and professor in an island of Greece with poorInternet connectivity. (2014)

Ninux Italy wifi No Experimentation and hacking culture. Ninux operates as an experimental platformfor decentralized protocols, policies and technologies. (2003)

Rhizomatica Mexico wireless YesProvides GSM services. Creates open-source technology and helps communities tobuild their own networks. Initiated by a small group of people with knowledge ofcommunity organization and technology. (2009)

Sarantaporo.gr Greece wireless Yes People with origins from the area of Sarantaporo wanted to create a website for theirvillage when they realized that there was no network connection. (2010)

TakNET Thailand wifi YesEstablished as an academic project at the Asian Institute of Technology (AIT). Followsthe goal of bridging the digital divide in Thailand villages. Composed of TakNET1,TakNET2 and TakNET3. (2012)

Wireless Leiden Netherlands wifi YesVolunteer-based open, inexpensive, fast wireless network in Leiden and surroundingvillages. Developed by a group of local residents. Provides Internet access and freelocal communication. (2002)

Zenzeleni.net South Africa wifiYes, VoIPpublicphones

Initiated by researchers from the University of the Western Cape (UWC) in the ruralunder-developed area of Mankosi. Solar powered network. Operated as an umbrellaco-operative enterprise and a telecoms provider. (2013)

TABLE I: Basic information about the 15 CN instances that are analyzed further in the survey. These are chosen as representative instancesof the rich variety of worldwide CNs.

A. Network Infrastructure Layers

Considering how a broadband network is created, its structurecan be decomposed into three distinct but inter-dependent layers:a) passive infrastructure, b) active infrastructure and c) services.

Passive infrastructure

Active infrastructure

Services

Fig. 2: The layers of a broadband network.

The passive infrastructure layer expresses the non-electronicphysical equipment needed to deploy the network. Non-electricelements vary depending on the link technology in use, e.g., fibre,copper, antennas. They typically refer to ducts, cables, masts,towers, technical premises, easements etc.The passive infrastructureis built to endure for many years, usually decades. Its development

demands high capital expenditure (CAPEX) and frequent upgradesare difficult to realize. However, its operational costs (OPEX) arerelatively low.

The second layer, i.e., active infrastructure, describesthe electronic physical equipment of a network such as routers,switches, transponders, control and management servers. The OPEXof the active equipment is high (i.e., electricity costs) but its capitalexpenditure is usually low since it involves up-to-date technologicalelements. The active equipment needs to follow the rapid advancesof technology and get renewed frequently, i.e., within a decade.

The third and highest layer of a broadband network is the layer ofservices. It corresponds to the telecommunication services providedon top of the passive and active infrastructure. These services maybe both private and public and include electronic government, ed-ucation, health, commerce, Internet, entertainment, telephony (e.g.,VoIP), access to media content (television, radio, movies) and manymore. End users usually pay a fee for receiving the services eitherdirectly or indirectly. The type of reimbursement depends on the cho-sen network infrastructure model and the business actors involved.

The implementation of the service layer is conditioned on the de-ployment of the passive and active infrastructure. Therefore, the firsttwo layers are a prerequisite for the existence of the third one (Fig.2).

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Acronym DescriptionAP Access PointCAPEX Capital ExpenditureCN Community NetworkCONFINE Community Networks Testbed for the Future InternetCPR Common Pool ResourceCS Community ServiceDIY Do-It-YourselfDNS Domain Name ServerEC European CommissionEU European UnionGFOSS Greek Free/Open Source Software SocietyICT Information and Communication TechnologyISP Internet Service ProviderITU International Telecommunications UnionMANET Mobile Ad-hoc NetworksNCL Network Commons LicenseNP Network ProviderNPO Non-Profit OrganizationOECD Organization for Economic Cooperation and DevelopmentOPEX Operational ExpenditureP2P Peer to PeerP2PWNC Peer-to-peer Wireless Network ConfederationPIP Physical Infrastructure ProviderSP Service ProviderVoIP Voice over Internet ProtocolWCED World Commission Environment and DevelopmentWCL Wireless Commons License

TABLE II: Terminology used throughout the paper.

B. Business actors

Business actors are determined in accordance with the networkinfrastructure layers [19],[48],[26],[62]. They are typically providersof the network’s equipment and services. Telecom operators andprivate companies, public authorities, local cooperatives and housingassociations, are some characteristic examples of business actors.

In detail, the physical infrastructure provider (PIP) hasownership of the passive equipment and undertakes the equipment’smaintenance and operation responsibilities. PIPs can be dividedinto backbone PIPs and access area PIPs, depending on whichnetwork parts they possess. Backbone PIPs invest in the backbonenetwork infrastructure, while access area PIPs own and moderatethe infrastructure aimed for providing connections to the end usersi.e., first-mile connectivity. In the case of CNs, a local organizationmay participate as a backbone PIP, an access PIP or both.

The network provider (NP) owns and operates the activeequipment. It leases physical infrastructure installations from thePIPs and makes its equipment available for the provision of servicesby other SPs or provides its own services. Network providers maybe public authorities, private companies, local cooperatives whoown the equipment or entities who are subcontracted to operatethem by one of the aforementioned owner entities.

The service provider offers services within the network. Serviceproviders are typically companies that utilize the network’s activeand passive equipment to offer their services to end users in ex-change for compensation, typically payment. The payment can be di-rect (service fee) or indirect (connection or network fee). They needaccess to the NP’s interface and install their own devices if and whereneeded. The existence of service provision within the network is vital

for the end user engagement and therefore the network’s viability.

C. Network Infrastructures Business Models

The roles and responsibilities of different business actors innetwork infrastructures vary resulting in a great range of businessmodels (Fig. 3). Traditional telecom models follow the concept ofvertical integration. In these models, the ownership and operationof all three infrastructure layers is concentrated to one single entity.As a consequence, cases of monopolies or oligopolies that hamperthe existence of competitors by exercising great control over themarket, i.e., ”market failure” cases, are common. Moreover, due tolack of other competing entities, a single vertical integrated operatoris often not willing to provide broadband access to remote areasfeaturing high network expansion costs, leaving several rural areasunder-served.

To reverse this picture, the ITU [19],[33] and the EC have seta goal to promote infrastructure separation and sharing throughlegislation, regulation and subsidies. Open access networks havebeen brought to focus.

The openness of a network is characterized by the presence ofmultiple providers in the market offering customers the opportunityto choose amongst them. Open access network models separatethe ownership of the business actors from the infrastructure layersi.e., PIP, NP, SP, with the aim of promoting competition, sharingof the network infrastructure and discouraging vertical integration.

The following cases can be distinguished although the limitsamong the respective actors are not always clearcut.

PIP – Physical Infrastructure ProviderNP – Network ProviderSP – Service Provider

LLUB – Local Loop Unbundling (Forzati 2010)

CPR

SP SP CSCS

CN

CPR – Common Pool ResourceCS – Community service

Fig. 3: The components of a broadband network (with a focus onoptical fibre) and the three service layers.

The different models differ in the functional separation acrosslayers, as recommended by ITU [33], ranging from verticalintegration across all layers in e, f, g, partial separation in a, b,d, and full functional separation in c. The models also differ interms of alternatives and therefore competition in each layer, exceptthe passive infrastructure, that tend to a single actor in charge ofdeploying and operating either the backbone or the access area PIP.While all models except g offer alternatives in service provision,only d, e provide alternatives in network provision.

Diverse types of local cooperative schemes fit and build onthese cases. Municipal networks focus on maximizing the access toconnectivity from public (municipal) interest, and they usually relyon public-private partnerships. The service is defined and governedby the public partner but implemented and operated by one or

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multiple private partners. Typical cases the optical fibre servicefrom Stokab in the Stockholm region, among several other regionsin Europe, following the d model, or the public WiFi servicesin most European cities, that can follow any model for serviceprovision, as the public entity just defines, funds and oversees thepublic service under private operation. Internet eXchange Points(IXP) are physical infrastructure through which Internet serviceproviders (ISPs) and Content Delivery Networks (CDNs) exchangeInternet traffic between their networks (autonomous systems). Theswitching infrastructure is built and managed as a CPR accordingto Fig.3, but the governance may range from a centralized a toa participatory CN model. IXPs and CNs are quite equivalent,the main difference being that IXPs connect larger entities only(wholesale) and CNs focus on individuals and households (retail).However the difference blurs as they expand, with the example ofguifi.net that is both a CN and a de-facto regional IXP, or the caseof Ninux, that acts like a country IXP of diverse city or regionalnetworks, and connected to the Rome IXP (Namex).

D. CNs as open access network instances: the commons model

CNs differ from other models in that there is crowdsourcing in alllayers. The community participants contribute and share the passiveinfrastructure, they also coordinate and operate the active network,and multiple service providers can benefit from that network infras-tructure CPR. Furthermore, CNs embody some key principles [6]:

Non-discriminatory and open access. The access is non-discriminatory because any pricing, when practiced, is determinedusing a cooperative, rather than competitive, model. Typically thisresults in a cost-oriented model (vs. market-oriented) applyingthe fair-trade principle for labour pricing [47]. It is open becauseeverybody has the right to join the infrastructure.

Open participation. Everybody has the right to join thecommunity. According to roles and interests, several main groupscould be identified as stakeholders: i) volunteers interested in aspectssuch as neutrality, privacy, independence, creativity, innovation, DIY,or protection of consumers rights; ii) commercial entities interestedin aspects such as demand, service supply, and stability of operation;iii) end users (i.e., customers), interested in network access andservice consumption; and iv) public agencies (local or national),interested in regulating the participation of society and the usageof public space, and even in satisfying their own telecommunicationneeds. Preserving a balance among these or other stakeholders isdesirable, as every group has natural attributions that should not bedelegated or undertaken by any other. It is important to clarify thatnot all stakeholders are present in all CNs. For instance, many CNsobject to the participation of commercial entities as this is againsttheir vision and philosophy (e.g. B4RN).

The model of the CN is based on the concept that the physicaland active equipment are used as a Common Pool Resource (CPR).Its participants must accept the rules to join the network andmust contribute the required infrastructure to do it (routers, links,and servers), but they keep the ownership of hardware they havecontributed and the right to withdraw. As a result, the infrastructureis shared and managed collectively, as a collective good.

Comparing the CN commons model with the aforementionedmodels for open access networks:

• the CPR (i.e., participants of the network, legal entity) replacesthe PIP and NP actors;

• the CPR offers access to private service providers (SPs) butalso provides community services (CSs).

Cooperation at the network deployment and operation level iscrucial but competition in the service provision is encouraged toavoid monopoly situations.

An example of the commons model in action is provided by theguifi.net CN. The network employs cost sharing and compensationmechanisms in order to facilitate the participation of commercialSPs and operators in the CN. They deliver their services through thenetwork’s infrastructure and receive payment from their customers.At the same time, they can contribute infrastructure and investmoney to the CPR or compensate the network for using it [5].

III. CN STAKEHOLDERS AND THE SUSTAINABILITY QUESTION

Sustainability is a multifaceted concept used to study a varietyof systems such as technical, biological and socio-cultural ones.Its precise definition depends on the system of interest. In general,the sustainability challenge consists in understanding the way thata system can smoothly operate in the present and develop in thefuture. Hence, sustainability is not a specific goal per se but acontinuous process to reach a goal. Although, originally the termwas used in an environmental context (United Nations WorldCommission on Environment and Development (WCED) 1987),it more recently acquired broader social and economical semantics(World Summit on Social Development, 2005).

Equally broad is the context of sustainability in the case of com-munity networks, which are by definition complex socio-technicalsystems. Contrary to the commercial production communication net-works, their existence per se is conditioned on the sustained and ac-tive participation of all its stakeholders, who contribute resources andgenerate value for it. Therefore, a sustainable network should firstof all ensure that all these actors, primarily end users, but also com-mercial service providers and public organizations when they arepresent, have proper commitments and incentives to contribute to thenetwork. This is not a trivial task since the participation of each actoris driven by different types of motives and aspirations, including eco-nomical, socio-cultural, and political ones. Hence, the network needsto put in place mechanisms, limits and incentive mechanisms toproperly address these aspirations, as in any commons regime [52].

The success of the CN to attract a critical mass of actors alsodetermines the funding alternatives of a CN. A sustainable fundingmodel, which will ensure the network capability to cover itsdeployment and maintenance expenses, is a crucial parameter forits long-term viability.

We review the practices of different CNs with respect to fundingin section IV. In the remainder of this section, we describe thebroadly varying motives met across and within the different actorsin a CN. Then, in section V, we describe how different CNs respondto these motives.

A. Volunteers

In the context of CNs, volunteers are the people who initiate theCN project. More often than not, (a subset of) these people takean active role in the network expansion, either through helping with

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the technical matters and/or organizing informational and trainingevents for potential participants [8].

The volunteer groups usually comprise of people that cumula-tively possess knowledge and expertise over a wide set of areas, in-cluding technical, legal, and finance matters [2]: technology enthusi-asts, radio amateurs, hackers, (social media) activists, and academics.It is not uncommon for volunteers to create a legal entity (Fig. 4) torepresent the network to third parties (i.e., government, third party or-ganizations, companies, Internet Service Providers (ISPs)). This letsthem have a voice and interface with third parties on legal and reg-ulatory matters, but also get involved in financial transactions (e.g.,collecting user subscriptions, fund raising, purchase of equipment).

Their motives have a strong bias towards political and socio-cultural values and ideals, which is not met in any of the otherthree stakeholder groups. Experimentation with technology, opensoftware and do-it-yourself (DIY) tools, sensitivity to privacyand network neutrality, the desire to bridge the digital divide, butalso commitment to the community spirit and social movement,participatory governance and decision-making, and protection ofconsumers’ rights, count as primary reasons for their involvement inCN initiatives. Economic motivations are much rarer; on the contrary,the members of the volunteers’ groups usually end up investing alot of personal effort, time, and money to the CN initiative, withoutdirect financial return of any kind. More specifically:

1) Socio-Economic motives: Socio-cultural motives often standbehind the original conception and deployment of CNs.

Bridging the digital divide: The right to (broadband)connectivity is a matter of equal opportunities in the contemporarydigital society; and digital illiteracy puts at disadvantage populationsdeprived of it. The launch of CN initiatives has many times beenthe response to poor or non-existent access to the Internet andInformation and Communication Technology (ICT) services. This istypically the case with remote, sparsely populated rural areas, wherecommercial operators are reluctant to invest on fixed broadbandinfrastructure because they do not deem this cost-efficient.

The initial volunteers’ group comes typically from local residentssuffering the digital divide (as the case is with the B4RN [30] andguifi networks [48]). However help may come from outside. In

the case of the Sarantaporo.gr network, in Greece, the CN cameout of the efforts of a small group of people living in Athens andabroad, with origins from the Sarantaporo area, by the time thatno broadband access alternative was available there. Likewise, thei4Free network in an island with poor Internet connectivity closeto the town of Nafpaktos, in Greece, started from the initiative ofa German engineer and professor. He created a small network at hisown expenses so that locals could have access to ICT services [48],[30], [46]. In a similar scenario, Peter Bloom, an American national,founded Rhizomatica to promote mobile-phone based services inthe rural area of Oaxaca, Mexico [58].

Economic incentives: these are in a sense relevant whenever aCN is set up in pursuit of cheaper (affordable) Internet access. Inthese cases, the underlying idea is how to expand coverage of theservice, ensure its sustainability and sovereignty from commercialdecisions, and save money with CNs compared to commercialalternatives rather than how to make money out of the CN initiative.

Therefore, in remote, sparsely populated areas, such as the ruralareas addressed by the B4RN initiative, the competing alternatives,where they exist, such as satellite or cellular, are typically moreexpensive and of lower quality. B4RN was conceived also as away to offer better connections at more affordable prices than itscompetitors, again in areas where these exist.

Another case, this time in urban environment, is the Consumenetwork in East London, UK, one of the very first CN initiativesin Europe. James Stevens ran a technology incubation businessoffering web, live streaming and video distribution services througha leased optic fiber connection. He came up with the idea toconnect buildings through wireless mesh links as a way to bypassthe expensive license costs and regulatory constraints related toexpanding the fiber communication across the buildings.

2) Political motives: Political causes often serve as driving forcesfor the groups that lead CN initiatives. Such causes often prove tobe strong enough to fuel these groups’ active involvement with theCN despite the effort, time and money this requires. They include:

Openness, net neutrality, and privacy: These highlycontroversial issues have served as primary motivations for CNinitiatives. The principle of net neutrality dictates that traffic withinthe network should be treated in an equal manner independentlyof the type of content or the source. The data communicated acrossthe network is not subject to discrimination.

A characteristic example of principles underlying the CNinitiatives is found in the declaration by the guifi.net Foundation,the volunteers’ group that has developed and still operates the guifiCN, in Catalonia, Spain [55], [7], [51]:

• Freedom to use the network, as long as the other users, thecontents, and the network itself are respected.

• Freedom to learn the working details of network elements andthe network as a whole.

• Freedom to disseminate the knowledge and the spirit of thenetwork.

• Freedom to offer services and contents.

Moreover, volunteers are often interested in accessing ICT serviceswithout having to compromise their privacy. This applies fortechnology enthusiasts, activists and users in general that wish toprotect their private content. CNs such as the French FFDN andthe German Freifunk declare privacy/anonymity and net neutrality

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as integral parts of their manifesto and incorporate them in theirfundamental operation principles.

Autonomy and alternative communication models: These arecommon motives for the original deployment and subsequentoperation of CNs [37], especially in urban areas, where the digitaldivide threat is much less pronounced. Community networks suchas Consume34 and Free2Air56 started out representing alternativeapproaches to the commercial Internet provision, aiming at higherfreedom and control over personal communications. In other cases,such as guifi.net, which started as an attempt to bridge the digitaldivide, such political purposes emerged as an equally strong motivat-ing factor, especially when the number of network connectivity al-ternatives increased. Rhizomatica founder goals were both to bridgethe digital divide and to create an alternate telecommunicationsnetwork where people could communicate with costs much lowerthan the existing telecom solutions in the area (where they existed).

3) Socio-cultural motives: Socio-cultural motives often standbehind the original conception and deployment of CNs. Amongthe main ones count:

Experimentation with technology and DIY culture: Severalinitiatives are driven by hackers, technology enthusiasts, andacademics who enjoy experimenting with network and radiotechnologies. The involvement within such a community presentsthem with a unique opportunity to further enhance their technicalknowledge and practice it over real networks.

The AWMN, Ninux, and Freifunk CNs were initiated and arestill run by network technicians and computer enthusiasts. As such,they have been characterized by a culture of experimentation andimprovisation. AWMN and Ninux, in particular are used by their vol-unteers as testbeds for manufacturing equipment (antennas, feeders)and experimenting with routing protocols and applications. This isevidenced also in the impressive number of native applications andservices that were developed for AWMN, without need for publicInternet connectivity, including games, libraries, network monitoringtools, DNS solutions, and experimental platforms. Notably, neitherAWMN nor Ninux, whose initials stand for ”No Internet, NetworkUnder eXperiment”, nominally provide Internet access.

Community spirit and altruism: Altruism, often coupled witha strong commitment to community ideals serve as importantmotivations for the active involvement of volunteers’ groups in CNs.

Both are strongly evidenced in the B4RN, Sarantaporo.gr andi4Free CN initiatives. Community activists have been among theleading figures in B4RN and have set it up as a community benefitsociety which can never be bought by a commercial operator and itsprofits can only be distributed to the community. Likewise, the Saran-taporo.gr non-profit organization involves people who are activistsin the area of commons and supporters of community ideals. Theyplace a lot of emphasis on cultivating these ideals in the residents ofthe area with parallel activities and social events. Finally, the leadingfigure behind the i4Free CN, identifies himself as a warm fan ofcommunity life and ideals. He has spent enormous amounts of timetrying to build a community around the CN through training andeducational events, even without much success as he admits [30].

3http://consume.net/4http://wiki.p2pfoundation.net/Consume5http://www.free2air.org/6http://wiki.p2pfoundation.net/Free2Air

B. Active participants

Even broader is the variety of reasons for the involvement ofcitizens in a community network. Decisive for many of them is theexpectation of available and abundant local connectivity anywhere isneeded. Furthermore there is the expectation of cheaper, or even free,Internet access and other services provided by commercial entities.For others, the CN represents a perfect opportunity to acquire newknowledge and experiment with technologies, and/or socialize andbecome part of a bigger community. Activism in favor of higherautonomy and data privacy are also evidenced as user participationmotives, albeit to a smaller extent than in volunteer groups.

Their levels of participation typical vary a lot within a CN.Some of them are highly active participating in events organizedby volunteers or other types of collective activities, sharing theirtechnical experience, developing applications and devoting personaltime and efforts to the CN. On the other extreme, a number of usersthat tends to be the majority in most CNs, set up a node and usethe CN to get Internet access or access to local services withoutfurther contributing to the activities of the community. However,the presence of even these passive users can benefit the networkto the extent that others can join the CN through their nodes.

The CN users may pay a connectivity fee for being part of the CNor not. These fees contribute to pay the necessary costs to upgrade ormaintain the CN infrastructure. Depending on whether they receivesome service over the CN, they may pay a consumption fee andmaintain a contributor, shareholder or customer relationship with theCN, directly or indirectly through paying service fees to a commer-cial service provider acting as intermediary and value-added reseller.

1) Socio-Economic motives: Users often expect benefits ofeconomic nature from their participation in a CN, both direct andindirect.

Direct economic benefits: The most usual one is local connectiv-ity or Internet access that is not offered by other providers, or at lowercost than alternative solutions, offered by commercial telecom oper-ators (Table I-B2). A characteristic example, Rhizomatica, has man-aged to reduce costs by 98% on international (U.S.) calls and 66% oncellphone calls. Internet connectivity can either be provided by theCNs themselves, which take on the role of alternative Internet serviceproviders (e.g., B4RN, Sarantaporo.gr); as an add-on service over theCN by a third party (e.g., guifi.net, Rhizomatica); or by CN memberswho pro bono share their access with other peers (e.g., AWMN).

The collective efforts of the CN participants is often fundamentalfor expanding the coverage of the network or lowering theconnectivity cost. For instance, B4RN partially crowdsources thecost and effort involved in deploying fiber in rural communitiesin Northern England. This way, it can offer fiber connectivity andInternet speed in underserved areas and at more favorable pricesthan alternative commercial solutions.

A local infrastructure, locally maintained, feeds the localeconomy, creating paid jobs for the deployment, maintenance,expansion and operation of the network itself and related servicesover the network (content and services) or enabled by the network(telework, remote assistance, surveillance, sensing).

CNs create the opportunity for local investment. Local canobtain economic benefits from investing in local infrastructures,particularly more durable fibre infrastructures, that can have goodreturns of investment from usage fees, while also giving indirect

8

economic benefits by increasing the value of households, typicallythe largest investment of a family.

Indirect economic benefits: Participation in a CN may incuradditional benefits to their users. One of them relates to the growth ofhuman capital and another to the added value that the CN generatesfor businesses and professionals participating in it. Examples fromSarantaporo.gr and AWMN show that young people (in the age of18-35) view the CNs as a path to information about job and furthereducation opportunities and to business activities developed aroundthe CN [30]. Moreover, in remote rural areas, network accessand Internet connectivity can enable professionals to search bettermarkets for their products and cheaper suppliers for their materials(e.g., farmers) and small business owners to join the network in theanticipation that visitors appreciate the Internet connectivity featurewhen choosing where to go (e.g., Sarantaporo.gr). Underservedcommunities in terms of connectivity tend to suffer from fragility orlack of other critical infrastructures. The deployment of networkinginfrastructures creates economies of sharing and bundling, suchas improvements in electrification, with the introduction of solarpanels, that for instance can enable or improve the quality ofnight-time lighting and food preservation, which in turn may createeconomic benefits from trading of these products.

2) Political motives: As seen in section III-A2, many CNshave been initiated under aspirations of privacy, net neutrality, andalternative models of Internet connectivity provision with strongflavor of autonomy and self-organization. The ideals underlying theinitial development of these CNs are often inherited by subsequentusers of the CN. However, these users tend to be a small part ofthe total CN user population. Typically, the larger the CN growsthe harder it becomes to find political causes that unite the wholecommunity behind them.

Openness, net neutrality and privacy: The aspects of privacyand neutrality have a strong role in CNs that utilize the Picopeeringagreement7 as a participation/operations framework and are partof the movement for open wireless radio networks8 (e.g., Freifunk,guifi.net, Ninux, FFDN).

The Picopeering agreement is a baseline template formalizing theinteraction between two network peers. It caters for a) an agreementon free exchange of data; b) an agreement on providence of opencommunication by publishing relevant peering information; c) noservice level guarantees; d) users’ formulations of use policies; ande) local amendments dependent on the will of node owners.

Autonomy and self-organization: The participation in CNgroups cultivates feelings of autonomy and self-organization. Selforganization is practised in the way new users connect to the CN,where they have to rely on their own resources and the voluntaryassistance of experienced network members. Being part of anindependent network satisfies personal ideological aspirations forself-organized network and autonomous use [37]. The abilityto participate in collective decision making and contribute to analternative ”commons”-based model of ICT access counts itselfas a worthy experience for users with strong ”commons” ideals.

3) Socio-cultural motives: A CN is a characteristic example ofparticipatory involvement, where users dedicate their efforts andtime to the network [63]. A number of services and applications

7http://www.picopeer.net/PPA-en.shtml8https://openwireless.org/.

combined with other activities that one way or another revolvearound the CN, offer users the opportunity to communicate, educateand entertain themselves, thus further motivating their participationin the network [62], [54].

Experimentation and training with ICT: Technologyenthusiasts participate in the network for experimenting with thetechnology i.e., trying software they develop and hacked code,make network speed measurements, play with network mappingand management tools [37]. Users can acquire new skills aboutcomputer and network use, i.e., either through self-experimentationor through training by network experts.

In CNs initiated by volunteers with technical background(e.g., AWMN, Ninux, Freifunk), the amount and type of services,applications and self-produced software increased greatly within thecommunity. Besides a variety of network monitoring tools, userscan enjoy communication services such as VoIP, online forums,mails, and instant messaging; data exchange services with servers,community clouds and file sharing systems; entertainment serviceswith gaming applications and audio/video broadcasting tools;information and educating services with online seminars, e-learningplatforms, and wikis.

Desire for social interaction: The smooth operation anddevelopment of a CN demands cooperation links at the networkinfrastructure level but also at the social level. In CNs, participantsare able to share their ideas and interests, participate in groups,interact and communicate with other network members just like theywould in any other online or physical community. Social networkingand communication tools raise great interest and remain active evenwhen other tools and services have a drop in their utilization.

The importance of local relationships in a CN [36] is alsoevidenced in three independent studies addressing a rural villagein Zambia [34], the TakNet CN, in the rural area of northernThailand [38], as well as Australian and Greek CNs in [37]. In thislast study, 91.2% of the users stated that they enjoyed interactingwith the community, 88% felt that their efforts would be returned byother community members and 80.5% expressed that the communityallowed them to work with people that they could trust and share sim-ilar interests. Likewise, in the case of TakNet, much of the activityamong users of the popular applications such as messaging, email,online social networks and gaming, exhibits a high degree of locality,i.e., people use Internet to interact with people within the same CN.

Socio-psychological motives: As social motives count socially-aware mechanisms that relate to concepts such as visibility, acknowl-edgment, social approval, individual privileges and status. Thissocial activity is applied within the networks’ technical limits [44].

The ability to compete with other people and satisfy one’s selfesteem through the involvement in the community, or receive acertain type of credit by others in the community, are motives not aseasy to distinguish but still present [37], [38], [34], [35] and withan impact on network growth and operation [61], [10].

C. Private sector service providers

Private sector service providers form the stakeholder type thatmay be less involved in CN initiatives. The term points to companies,ISPs, small businesses or individuals, namely entities that support oruse the network to provide some service and get compensated for it.These can be a) the professionals that are involved in the installation,

9

CN Legal form FundingAWMN AWMN Foundation Members (individually)B4RN Community Benefit Society MembersConsume None Central actorsFFDN Non-Profit Organization Members, Local authorities, DonationsFree2Air Incorporated Legal Company MembersFreifunk Non-Profit Organization Members, Public InstitutionsFunkfeuer None Membersguifi.net Guifi.net Foundation Membersi4Free None Central actorNinux None Members

Rhizomatica Non-Profit OrganizationMembers, National and Internationalorganizations, Donations

Sarantaporo.gr Non-Profit Organization Members, European Union, Donations

TakNET Social enterprise - Net2homeMembers, Private Insitutions, THNICFoundation, European Union

Wireless Leiden Non-Profit Organization Members, Public/Private InstitutionsZenzeleni.net Formal Network/Telecom Operator Members, Public Institutions

TABLE III: CN specific organizational aspects.

operation and maintenance of the CPR network infrastructure, orb) the organizations that provide content or services inside the CN.At first glance, these entities do over the CN what they do overany other network, i.e., provide services where there is demandfor them. However, the legal provisions and conditions of runningbusiness over the CN may be different given the existence of a CPRinfrastructure and the governance and the crowdsourced nature of it.In fact, the CPR is an enabler of small private sector providers. Sincethe network commons is a shared resource, that enables these smallplayers to operate and provide services over a larger population, withthe economies of scale of cooperative aggregation of CAPEX andOPEX among multiple participants, and the complementarity andopportunities of specialization among them. This also means a lowerbarrier or entry, with much less initial investment and less risk thanksto the cooperative, and cost oriented model, of the network commons.Therefore the network infrastructure commons becomes a criticalresource for the operation and competitiveness of these local privatesector service providers. Therefore the common goal would bepreserving the commons to enable their specific business models.

The incentives for the participation of private sector serviceproviders in the network are almost always economic. These actorsare interested in profit. The CN provides them with access topotential customers who would otherwise be unreachable. Theimplementation of their commercial activities depends on theorganizational nature of the CN. Guifi.net has set up a frameworkthat enables the participation of private sector in its CN, includingmaintainers, installers, ISP providers, VoIP providers (Table III-C).These entities may sign agreements with the guifi.net Foundation,when the service provision has to do with the sustainability ofthe CPR. External Over-The-Top (OTT) services, such as InternetVOIP, Video, content providers are left outside. In Rhizomatica,ISPs and VOIP providers are key partners of the organization.Rhizomatica provides the Radio Access Network through which theservice providers reach the local communities and their CN users.

D. Public agenciesPublic agencies have the natural role of regulating the public

space, either for service provision, occupation of public spectrum,public land, but also supporting local development and ensuring ac-cess rights to public information and services. Public agencies havea responsibility to regulate the deployment and service provision ofCNs, as with any other entity performing these activities. Further-more, they may cooperate with a CN when the mission of both align.They may contribute to its deployment and growth through fundingthe initiative, sponsoring network equipment, consuming CN ser-vices, facilitating its expansion and growth or by permitting the useof public space and resources by a CN. In Catalonia, the Foundationoperating guifi.net has developed the Universal format [50], atemplate municipal ordinance, that allows municipalities to regulatepublic, commercial and community entities to deploy sharedinfrastructures in public space. Under these principles, several localauthorities have allowed guifi.net groups to dig public space andlay down fiber for expanding the network. In several German cities,Freifunk is given the permission to set up antennas and equipmentin the roof top of churches, Town Halls, or other public buildings.

Quite often other types of public agencies get involved in thenetwork. Sarantaporo.gr has received network equipment forthe initial deployment by the Greek Foundation for open-sourcesoftware and Internet connectivity from the regional Universityof Applied Sciences. TakNet received financial support from theThai Network Information Centre Foundation and initial equipmentdonation and support from the Network Startup Resource Centre.

Depending on their level of participation public agencies cansign collaboration agreements with the legal entity of the CN andcontribute economic or infrastructure resources with or withoutcompensation.

1) Socio-economic motives: The participation of public agenciesin a CN initiative can also have an economic motivation. In thecase of guifi.net public agencies can fund the network expansionthrough purchase of equipment in return for complimentary addedvalue services over the CN. Public agencies may be interested in

10

Services Private sector providers

Internet Service Provider (ISP)

Adit Slu, Ballus Informatica, Capa8, Cittec, Delanit, Del-Internet Telecom, Ebrecom, EmpordaWifi - Guifi.net a l’Alt Emporda, Girona Fibra, Goufone, Indaleccius Broadcasting, Pangea.org,Priona.net, S.G. Electronics, Steitec-Servei Tecnic d’Electronica i Telecomunicacions, Ticae,Xartic

Mobile ProviderBallus Informatica, Capa8, Cittec, Delanit, Ebrecom, Emporda Wifi - Guifi.net al Alt Emporda,Girona Fibra, Goufone, Indaleccius Broadcasting, Priona.net, S.G.Electronics, Ticae

SurveillanceBallus Informatica S.L., Capa8, Delanit, Ebrecom, Girona Fibra, Goufone, Matwifi, S.G.Electronics, Ticae

Telephony (VoIP) ProviderBallus Informatica, Capa8, Cittec, Delanit, Del-Internet Telecom, Ebrecom, Emporda Wifi- Guifi.net a l’Alt Emporda, Girona Fibra, Goufone, Indaleccius Broadcasting, Matwifi,Priona.net, S.G. Electronics, Ticae

TV (IpTv) Provider Delanit, Del-Internet Telecom, Indaleccius Broadcasting, Priona.netAgreement types Service providersEconomic Activity Agreement Adit Slu, Asociacion SevillaGuifi, Associacio Guifinet la Bisbal d’Emporda, Ballus Informatica,

Capa8, Cittec, Delanit, Del-Internet Telecom, Ebrecom, Emporda Wifi - Guifi.net al AltEmporda, Girona Fibra, Goufone, Indaleccius Broadcasting, Ion Alejos Garizabal, MaiderLikona, Matwifi, Pangea.org, Priona.net, S.G.Electronics, Steitec- Servei Tecnin d’ElectronicaI Telecomunicacions, Ticae, Xartic

Volunteer Agreement Cittec, Girona Fibra, Matwifi

TABLE IV: Private sector service providers in guifi.net and the services they provide.

the added value of purchasing connectivity services from a CPRinfrastructure, as while being competitive in price, can amplifythe spill-over effects in the local economy, and contribute tosocio-economic development. However, public entities may also betempted to put obstacles as a result of the influence and pressure oftraditional large telecom companies, with more taxation than largetelecom or Internet players that may enjoy unfair tax benefits.

2) Political motives: The participation of public agencies in a CNoften comes as a result of high-level policies against the digital di-vide, to increase the offer or lower the costs of local connectivity, andin favor of equal opportunities in the digital economy and society.

3) Socio-cultural motives: Public agencies may also supportCNs because they acknowledge their long-term potential tostrengthen the community links, raise awareness for issuesconcerning the local societies and favor the engagement of citizenswith the commons. On the polar opposite and more opportunisticnote, local administrations (such as municipalities) can advertisethe provision of network services as a political achievement thatincreases their re-election chances.

IV. FUNDING SOURCES FOR CNS

CNs use one or more of the following ways (Table III-B3) tofund their activities [4]:

A. Member subscriptions and contributions in kind

This is the most common funding model for CNs. In this case, themembers of the CN contribute network equipment and time/effort tothe network growth and maintenance. In the case of the BARN net-work, which provides fibre connectivity, members even contributeddigging effort. In most cases, the CN users pay a monthly/annualsubscription fee for the CN needs. Several CNs such as AWMNin Greece, Ninux.net in Italy, BARN in UK, and Freifunk.net inGermany, have managed to scale significantly this way.

Despite its simplicity, the model has several variations.Subscriptions may be mandatory or voluntary; or they may serve as

a prerequisite for participation in decision-making bodies and votingrights. In the case of the Sarantaporo.gr, it is villages under thenetwork coverage, rather than individual CN users, that are chargedwith a fee. How each village will split the cost among local usersis left to the the CN participants in that specific village to define.

What the CN users get in return for their subscriptions is closelyrelated to the way the CN organizes itself and positions in thetelecommunications arena. For example, B4RN operates as acommunity benefit society, which provides Internet service to itssubscribers. The subscription model is composed of a connectivityfee and different service fees for different types of users. On a similarnote, Zenzeleni.net operates as a cooperative telecommunicationsoperator providing voice and data services to its customers. TakNethas developed a social enterprise called Net2Home. Users have topay monthly fees that are used for covering fiber (to the networkoperator), maintenance, equipment installation, technical onlinesupport, network management and monitoring costs. Rhizomaticahelps communities in Mexico build their networks receives a flatrate for equipment installation and community member training aswell as a percentage of monthly subscription, advisory and technicalservices fees. Finally, but far more rarely, a CN may operate asa for-profit company. Some of the FFDN networks in France arecommercial networks that indeed rely on policies such as standardpay-per-use contracts and added value services to customersoutside the CN. However, in contrast with traditional commercialcompanies that extract profit from customers and locals to retributeinvestors, CNs reinvest the profits in the CPR infrastructure.

B. Donations from supporters

Community Networks are often financed through crowd-fundingprojects or direct, regular or one-time, donations. In some CNs,citizens can invest in the infrastructure, either for a specific reasonsuch as crowdfunding the construction or improvement of a criticallink that affects the user (typical in guifi.net), or generic, throughcommunity shares to expand the local network or even his homeaccess (in B4RN). These investments can generate tax returns

11

(guifi.net Foundation or B4RN). In B4RN this investment alsogenerates (3%) interest after the third year. In developing areasor in disaster situations external donors can contribute funds suchas in Zenzeleni (ZA), Rhizomatica and Nepal Wireless (NP). Thisfunding source typically complements other funding sources sinceit rarely suffices to cover the CN’s funding needs.

C. Support from public agencies and institutions

There are cases, where CN initiatives have got generous supportfrom public funds (cash or in kind). Municipalities and localauthorities emerge as main actors in this respect. The synergy ofcommons/public service with civil society/municipality can limitthe survival concerns of CNs as far as one finds sustainable modelsthat motivate their cooperation [25], [57],[56].

One such case is the Sarantaporo.gr CN, which set up its firstnodes with hardware and equipment received from the GreekFree/Open source Software Society (GFOSS); and, later, expandedthe CN through funding by the CONFINE project [11], fundedby the European Commission. Likewise, in the case of Freifunk,the support from public authorities was expressed through makingavailable public buildings such as churches or Town Halls forplacing and storing the network’s equipment (e.g., antennas).

Sometimes, the support may be expressed in more indirect, yetequally significant, ways such as giving proper attention to CNsin regulatory actions. The guifi.net Foundation has developed acooperative infrastructure sharing model (the Universal deploymentmodel) that develops over the Directive 2014/61/CE on broadbandcost reduction of the EU9 and the infrastructure sharing concept ofthe ITU10. The model prescribes how municipalities and countiescan regulate the use of public space by private, government and civilsociety in a sustainable manner [50]. Rhizomatica has expressedinterest in following a compensation system such as the one usedin guifi.net [58].

0

0,5

1

1,5

2

2,5

3AWMN

B4RN

Consume

FFDN

Free2Air

Freifunk

Funkfeuer

guifi.neti4Free

Rhizomatica

Ninux

Sarantaporo.gr

TakNET

Wireless Leiden

Zenzeleni.net

Funding entities

Fig. 5: Radar chart with CN funding entities in a 0-3 scale. CNfunding sources. 0: mainly private entities’ involvement, 1: mainlypublic agencies’ involvement, small scale member contribution2: mainly member contribution (donations, non regular fees), 3:member contribution only (regular fees).

9https://ec.europa.eu/digital-single-market/en/news/factsheets-directive-201461ce-broadband-cost-reduction

10https://www.itu.int/ITU-D/treg/publications/Trends08 exec A5-e.pdf

D. Funding from private sector through commons-based policies

In the case of guifi.net, CNs have come up with unique innovativemodels combining voluntary and professional services into acommons-based approach. Commercial service providers offerservices over the CN and charge the CN users as typical customers,but also subsidize the CN growth and maintenance subscribing tothe commons policies. This way, the CN maintains its non-profitorientation and pursues its sustainability through synergies withentities undertaking commercial for-profit activities [5].

When assessing the strengths and weaknesses of the fourcategories of funding sources, the following remarks are due:

• Some sources (i.e., donations, voluntary contributions etc.)are one way or another not guaranteed and they makelong-term strategic planning difficult. They could also lead todisagreements and conflicts between CN members concerningtheir distribution inside the network, especially if there are notwell-defined decision-making processes.

• Unless something dramatically changes on the regulationside, the support of public authorities for CNs cannot betaken for granted. BARN is one CN instance that tried toaccess national funding without success (their bid for thefunding was eventually withdrawn). In the case of guifi.net,the municipality of Barcelona is reluctant to provide the CNwith access to the city wi-fi and fiber infrastructure. In general,CNs tend to view access to local, national or European fundstoo difficult as well as demanding, uncertain, and bureaucratic.

• The dominant view across CN initiatives is that the fundingfrom own resources is the most reliable and favorable option.BARN and Freifunk, two of the three networks in Europethat have managed to scale in the order of tens of thousandsof nodes, have followed this approach.

• Trying to put commercial service providers in the loop whilepreserving the CN ideals, as guifi.net does, definitely representsan innovative approach. The success it experiences in the caseof the guifi network renders it a valid funding model alternative.

Interestingly, only guifi.net so far has managed to involve in itsfunding model all possible actors (end users/members, privatesector and public authorities). Striking the right balance betweenthe roles and contribution modes of these three parts may provethe key towards the economic sustainability of CN initiatives.

Fig. 5 summarizes the funding dependencies on different sourcesfor the 15 CNs. Member contributions, public or private institutions,public authorities, contests and funding projects are met in differentscales within each CN and provide part (or all) of the network’sresources. Some CNs operate through regular economic contri-butions of their members in commercialized subscription models(B4RN, Zenzeleni.net, FFDN, Rhizomatica) while others adhere tonon regular fees usually gathered in the form of donations by theirmembers (AWMN, Freifunk, Funkfeuer). In cases where the contri-butions by a CN’s own members are not systematic, public fundings(Sarantaporo.gr, TakNET) pose a significant aid and private entityinvolvement contributes to the economic activity of the CN (i4Free,guifi.net, Wireless Leiden). The involvement of private entities variesamong a single person’s funding met in i4Free, ISP’s offering theirservices and contributing to the ecosystem of the CN in guifi.net, orprivate and public funding by institutions in Wireless Leiden.

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V. INCENTIVE MECHANISMS IN CNS

To ensure a sustainable presence, CNs have put in place diverseincentive mechanisms. As with other types of commons [52], themain purpose of these mechanisms is to limit, encourage and fuelthe original motives for participation of all types of actors. Theyalso aim to prevent phenomena and conditions that might weakenthe original motivation of actors. Such phenomena include mainly:

Free riding and selfish behaviors: many users are solely interestedin enjoying network connectivity without themselves contributingadequate or any resources to the CN. Such behaviors can easily leadto the depletion of network resources and CN degradation. Mech-anisms for organizing and ensuring users sustained contributionsand distributing effort across them are of significant importance.

Unclear CN legal status: CN actors (users or private sectorentities) may be deterred from joining the network and participatingin its activities if its legal status is not clear. Well establishedoperational and participation rules can alleviate such effects.

In what follows, we review incentive mechanisms that are either inplace in different CNs or have been proposed, without (yet) finding apath to implementation, in the literature. In the latter context, we alsoreview mechanisms that have been proposed for similar systemssuch as wireless ad-hoc networks, P2P systems, and virtual onlinecommunities. These systems display inherent structural similaritieswith CNs in that they also depend on the collective effort and coop-eration of their participants to fulfill their tasks: forward and routedata in wireless ad hoc networks, disseminate files and other datain P2P systems, share effort and data in virtual online communities.

The different incentive mechanisms aiming to motivate theparticipation in CNs and strengthen their sustainability are groupedinto six categories (Fig. 6).

Fig. 6: Categories of incentive mechanisms used in CNs.

A. Enforcing fairness in users’ contributions and interactions

Despite the direct threat that free riding phenomena poseto the network’s long-term sustainability, actual preventioncountermeasures are not that widespread in most CNs, with thenotable exception of guifi.net [6]. Interestingly, a quite broad rangeof solutions have been proposed in the literature, either in thespecific context of CNs or that of similar systems (wireless ad-hoc,P2P, and online virtual communities) [32], [15].

1) Direct reciprocity-based mechanisms: Reciprocity is a broadterm that incorporates the notion of human cooperation in differentinteraction scenarios [49]. Direct reciprocity keeps records of the

interaction of two specific individuals so that the accounts aresettled between those two. The ”tit-for-tat” manner of connectingto wireless CNs is quite common practice between their members.For a node to connect to a CN, there must be another node to whichthe connection is directed. In many cases, the reciprocal sharingobligations stemming from the participation in the CN, are explicitlydescribed in licenses such as the Wireless Commons License(WCL)[6]11 defined in terms of neutrality and general reciprocation.

Direct reciprocity mechanisms can be described in variouscontexts such as in sharing network connectivity or storage andcomputing resources. The compensation tables in guifi.net is akey resource to ensure the economic sustainability of the network,ensuring a cooperative and cost-oriented model to share the recurringcosts and balance investment, maintenance and consumption [5].

In terms of proposals, connectivity sharing is the objectivestudied in [18]. A reciprocity algorithm, coupled with the P2PWNCprotocol in [17], keeps account of the services each participantprovides and consumes via technical receipts. This way, it keepsa balance between the amount of traffic users transfer andthat they relay on behalf of others. The model considers theprovision of Internet access through the APs of a wireless CN.Participants are divided into teams that manage their own APs andconsume/contribute traffic of/to another AP.

Reciprocity-based mechanisms for sharing storage andcomputing resources are reported in [14], [13] and [64]. In [14]and [13], the reciprocity-based mechanism is implemented overa Community Cloud made out of shared computational resources ofthe network members and is based on records of participants’ efforts.Results indicate that the most suitable structure for communityclouds should distinguish between ordinary nodes that possesscloud resources and super nodes that are responsible for themanagement of resource sharing. In [64], mobile devices used forcomputing, borrow CPU slots in a reciprocal manner. It is suggestedthat the heterogeneity in the amount of available resources may notbe beneficial for participants with large-scale resources.

2) Indirect reciprocity-based mechanisms: The concept of directreciprocity readily expands to that of indirect reciprocity, which isessentially realized by reputation mechanisms. Indirect reciprocitydoes not consider two specific individuals (like direct reciprocity)but rather asymmetric random exchanges based on the reputationscores of each individual node. Key issues in building reputationmechanisms [12], involve keeping past behavior records (as nodereputation is partially built over time), carefully evaluating all ofthe acquired information and distinguishing between old data vsrecently gathered ones. Among other challenges, reputation-basedsystems have to face the impact of liars on peer reputation i.e.,nodes giving unreliable information about other nodes. The systemshould be able to yield immediate response to known misbehavingnodes by drawing from past information.

The guifi.net classification of suppliers12 (professionals,volunteers) provides a public ranked list according to reputationof professionals and volunteers available for a range of tasks. Thelist is based on the certification of their abilities based on actualdeployments or training courses.

11http://wiki.p2pfoundation.net/Wireless Commons License12https://guifi.net/en/node/3671/suppliers

13

Reputation mechanisms have been proposed for P2P systems andwireless ad-hoc networks. In [59], such a mechanism is developedto build a reputation score for P2P system participants. Each peeris described based on how much service (bandwidth, computation)it provides and consumes. Peers are encouraged to collaborate witheach other and receive an increase in their reputation metrics. Themechanism successfully results in peers making coalitions thateventually work to their benefit. In a similar rationale for routing inmobile ad-hoc networks (MANETs), the reputation technique aimsat isolating non-cooperative node behavior using the Confidantprotocol. The tamper-proof hardware, which is embedded in nodes,keeps account of their virtual credit collected as they contribute inpacket forwarding. The reputation mechanism in [45] keeps recordsof the collaboration activities of nodes in the MANET and buildsa reputation score for each node, based on monitored collaborationdata and information input from other nodes.

3) Punishment of free-riders: Free riding is a quite common prob-lem in commons, experienced in various forms by each network type.The design of long-enduring CPR institutions [52] requires gradu-ated sanctions for appropriators who do not respect community rules.

This implies defining the “boundaries”, determined by thecommunity license and agreements, and requires effective conflictresolution methods that may include sanctions [6]. The conflictsresolution system in guifi.net provides a systematic and clearprocedure for resolution of conflicts with participants that negativelyaffect the common infrastructure resource, with a scale of graduatedsanctions. It consists of three stages -conciliation, mediation, andarbitration- all of them driven by a lawyer chosen from a set ofvolunteers. This has been found critical to keep the infrastructureand the project itself operational.

In multi-hop wireless networks, consumption of bandwidth andenergy serve as the main motivations for nodes’ free riding behavior.Nodes enjoy packet forwarding of their own packets by othernodes but defer, either deterministically or probabilistically, fromforwarding the packet of other nodes. Detection and punishmentof suspected free-riding nodes are the two basic steps suggestedfor dealing with this phenomenon in the corresponding literature.

In the generic setting in [53], it is suggested that free ridingshould be confronted using exclusion of peers from a group as aplausible threat. Misbehaving nodes are detected through reputationprotocols and excluded from the network or community. Detectionof selfish behaviors of mesh routing nodes is carried out in [43]with a trust-based mechanism. The mechanism can be developedbased on the combined observations of neighbor (and other) nodesof the CN such as in KDet [39]. The Catch protocol in [41], tries tolimit the free riding problem in multi-hop wireless networks whilepreserving anonymity. The adopted technique uses anonymousmessages and statistical tests to detect the selfishly behaving nodesand isolate them. It relies on the assumption that free-riding doesnot appear in the initial stages of the network deployment but later,as the number of peers starts to grow. The corresponding examplein CNs reflects the fact that the initial members, i.e., volunteers,create the CNs based on certain principles and knowledge that arenot compatible with free riding practice. Members that join thenetwork in subsequent stages, i.e., users, are often not acquaintedwith these principles and the importance of complying to them.

4) Direct and indirect financial compensation: This type ofmechanisms aim to support CNs’ economic sustainability. Guifi.net,

a representative example of this category, involves private sectoractors that provide commercial services in the CN. To this end, ithas set forth additional mechanisms for compensating contributionsof different stakeholders i.e., compensation system, provision ofdonation certificates [5].

The compensation system aims at settling imbalances betweennetwork usage and contributions (CAPEX or OPEX). It is a wayfor participating entities to share network costs while acquiringnetwork resources. Private sector service providers may assumethe roles of operators that contribute to the network and consumeits resources, investors that only contribute, and pure operators thatonly consume network resources. Operators can contribute eitherto the deployment of the infrastructure or to its maintenance.

The provision of donation certificates that are amenable to taxdeductions, is a way of acquiring indirect benefits for contributingto a commons infrastructure. Users who pay commercial serviceproviders for service provision, can have some tax deductionbenefits as well according to the Spanish legislation and regulationauthorities.

Other mechanisms explored in the literature but not yet validatedin CNs are the following.

5) Community currencies: The design of community currenciesis a way to enforce reciprocity and balance the contributions of nodesto the network. As long as the cost/value of nodes’ contribution canbe quantified, community currencies can ease the exchange of awider set of services between CN members and users of a CN andproperly reward voluntary activities. At the same time, communitycurrencies are themselves collaborative activities that increasethe community spirit and strengthen the intrinsic motivations forparticipating in a CN. In fact, the smooth operation of a communitycurrency depends heavily on building trust between communitymembers both to accept and use the corresponding currency but alsoto be able to provide risk-free credits that are very important for therequired flow of currency. This trust is a very important asset thatcan play a key role in the initial birth and sustainable operation ofCNs. For the same reason (existing trust and community values), theexistence and operation of a CN eases the launch of a communitycurrency. The development of community currencies for CNs isyet at an initial stage but they pose a promising mechanism thatexhibits a complex bidirectional relation with CNs [4].

6) Other game-theoretic mechanisms for enforcing participation:Participant’s motives for contributing in CNs can be enhanced bygame-theoretic and mechanism design approaches. An incentivemechanism based on a Stackelberg game is provided in [9]. Theobjective is to stimulate user and ISP provider participation in ahypothesis of a global CN where the participating entities (usersand ISPs) interact with an intermediate entity, i.e., the communityprovider or mediator.

Due to the cooperative nature of CNs, participation of peersoften needs to be combined with mutual cooperation i.e.,forwarding packets, amongst them. While some works usereputation-based mechanisms there are others that prefer credit asa plausible economic incentive to sustain participation. The worksin [21], [22], [67] and [66] tackle this objective in different typesof systems i.e., P2P, static or mobile ad-hoc systems.

In a P2P network setting [21], the prisoner’s dilemma is chosento design incentive techniques and deal with challenges such aslarge populations with small lifetime, asymmetry of interest in

14

participation and multiple peer identities. In order to enhancecooperation and avoid false identities and hijacking, the mechanismproposes to keep records of peer interaction and use them to buildreputation metrics. In another approach, the work in [22] uses gametheory techniques to enhance cooperation in static ad-hoc networksand suggests that the most effective incentivizing structure is onethat combines actual incentive mechanisms i.e., actual credits asreputation systems or virtual currencies, with mechanisms thattarget players’ self interest and enjoyment. A Video on Demandservice on wireless ad hoc systems is the setting for the Stackelberggame presented in [65]. In order to promote cooperation amongparticipants i.e., upload and forward data, the content provideroffers them rewards which vary across actual payment, virtualcredit or reputation points. A software protocol in [67] combinedwith a game-theoretic aspect is used to stimulate cooperationamong selfish nodes in mobile ad-hoc networks. A cheat-proof andcredit-based mechanism determines node rewards and costs whichare utilized for packet forwarding and route discovery.

B. Community cloud infrastructure

CN services and applications that store data or process locallycan serve as privacy-related incentive mechanisms for CNparticipants avoiding the exposure to not well understood and oftenprivacy-unfriendly practices of commercial data storage solutions.More often than not, such services involve the deployment ofdistributed cloud solutions that are deployed locally across the CNnodes, that process and store users’ data without dependence onexternal cloud services.

A proposition to extend CN resource sharing beyond bandwidthresources to computing resources can be found and discussedin [35]. Cloud computing infrastructures can be developed invarious ways but face severe challenges due to the nature ofCNs i.e., hardware and software diversity with various optionsfor inexpensive material, decentralized management where userscontribute and manage their own resources and rapid changes in thenumber of contributing nodes. The idea of developing a distributedCommunity Cloud that follows the topology of CNs is proposedin [14]. The goal is to regulate consumption and contribution ofparticipant resources in the community cloud in accordance toone’s level of contribution. They present an effort-based mechanismfor stimulating node participation in resource sharing. Nodes areincentivized using rewards that depend upon their contribution, i.e.,effort to the local cloud system. A Community Cloud can also beused in conjunction with Grid Computing techniques [42]. TheCommunity Cloud uses the spare resources of network nodes whileconsidering environmental sustainability and self-management andreplaces vendor clouds with full access to users’ resources.

C. Socializing processes and tools

CNs have developed a great variety of mechanisms to promoteparticipation, interaction and knowledge dissemination amongCN members i.e., social events, meetings, new member inductionprocess. These mechanisms serve as a ”social” incentive toencourage active involvement and engage new and old membersto CN processes and operation.

1) Social events and meetings: Large- and small-scale CNs orga-nize gatherings and events to discuss not only CN organizational mat-ters but also strengthen the bonds of community members throughsocial activities. Face to face meetings are common practices.Depending on their morphology i.e., a single network or network ofnetworks, CN members have meetings weekly, monthly or annually.CNs which are composed of smaller networks (guifi.net, Ninux,Freifunk), tend to have weekly or monthly face to face meeting at thelocal networks and an annual global meeting to get together and dis-cuss the issues arising from the operation of the entire network. OtherCNs like AMWN, schedule frequent meetings (i.e., General Assem-bly) when important organizational matters are up for discussion.

2) New member induction processes: Depending on thementality and philosophy of the particular CN, interaction withnetwork members is a natural prerequisite for a newcomer’s accessto the network. The way that this interaction is later on retained,is possible to determine their individual participation level. Forexample in AWMN or guifi.net, new participants are urged toregister and communicate with nodes of physical proximity to them.After communicating with the node owners, they are able to receiveadvice about the equipment they need and acquire assistance fromexisting members in setting up their own nodes and joining thenetwork. Many node owners provide public contact information forothers to contact them. In cases, where actual interaction with nodeowners is not possible or for complementary assistance, users canregister to the website and post their questions in the CN’s forum.

D. Education and training practices

Education and training of CN members is an important aspectof CNs, addressing their members desire for acquiring new skillsand learn more about networking and radio technologies. Seminars,workshops and online manuals are the main deliverables of this lineof effort, invested typically by members of the volunteers’ groupbut also by other CN members.

1) Workshops and seminars: Several workshop and seminarevents are organized by existing CNs (AWMN, Sarantaporo.gr,guifi.net). Experienced members share their knowledge with newmembers, exchange ideas and present available technical solutions.Guifi.net is quite active in organizing workshops and trainingseminars i.e., guifi labs13 14, the SAX15, or supports related eventsFOSDEM16, the Dynamic Coalition on Community Connectivity(DC3)17.

AWMN workshops aim at enhancing members’ technical skillsby disseminating knowledge and technical expertise, interactingwith people that have the same interests, strengthening thebonds within the community and new member training. In adifferent approach, Sarantaporo.gr workshops are more focusedto the broader community of locals (with or without technicalexpertise), inform people about the operation of the network andshare knowledge over the wireless networking principles and thedevelopment of community networks.

13http://www.guifiraval.net/14https://guifi.net/en/event15https://sax2016.guifi.net16Free and Open Source Software Developers’ European Meeting:

https://en.wikipedia.org/wiki/FOSDEM17https://www.intgovforum.org/cms/175-igf-2015/

3014-dynamic-coalition-on-community-connectivity-dc3

15

2) Online material for DIY fans: CNs invest effort to derivemanuals and how-to documents so that users can learn more abouttechnical matters and be able to set up their own nodes. Freifunk,Ninux, AWMN, guifi.net follow this practice and develop guidesthat provide technical instructions on actions and requirements ofsetting up nodes, FAQs and other useful information. Participants areencouraged to self-educate and ”take matters into their own hands”instead of relying to ”experts” and behaving as consumers of service.In cases, where online material is not enough they can always getadvice in CN forums, or retrieve contact info of node owners.

E. Local applications and services as incentives

The applications running over the network can themselves beconsidered as mechanisms motivating persons to join the network18.Such services range from network connectivity to communicationand entertainment.

1) Proposed services: The CN literature has shown specialinterest in services such as VoIP, community clouds andcrowdsourcing applications. Trusted VoIP service for nomadicusers in wireless network scenarios is the subject of [16], [28]and [29]. Building upon an existing scheme, the Peer-to-peerWireless Network Confederation (P2PWNC), the work in [16],develops a VoIP scheme utilizing residential Wireless LAN accesspoints (producers of bandwidth) for nomadic users (consumers ofbandwidth) as a low cost alternative to traditional GSM telephony.In another generic setting in [28] and [29], authors experiment withVoIP services for nomadic users using community-based Internetaccess and identify their perceived challenges (trust on nodes, dataprivacy and unspecified conditions of the wireless environment)and performance limits (capacity, service quality, security).

Cloud services have also attracted a lot of attention asfundamental privacy enablers, i.e., for storing the data of the CNlocally, without needing to interact with the public Internet. Adetailed discussion on clouds can be found in section V-B.

Crowdsourcing applications have the potential to match verywell the participatory nature of wireless community networks, i.e.,participatory networking [63] and the strong community-orientedsocial structure met in most developing regions. In the crowdsourc-ing paradigm, individual users solicit information, content or servicefrom groups of people. The community dimension only strengthensthe case for such applications since the community bonds serve asadditional socio-psychological incentives for the active participationand contributions of end users. The common resources shared by themembers can serve as the media where users (mobile or not) connectto post tasks or get informed about available task announcements.Users receive explicit rewards such as monetary payments, virtualcredits of services that match the services they offer [40].

2) Implemented services: Certain CNs have implemented abroad variety of services and applications, while others are at amore initial stage of service and application provision. In CNs likeSarantaporo.gr and i4Free, the main service of interest is Internetaccess. Yet, Internet access is not always on offer by the CN: Ninuxdoes not provide any Internet service at all; guifi.net offers the abilityonly through private Internet service providers operating over the

18There are arguments both in favour of the importance of local services inCNs [3], but also doubts that local services can make an impact on CNs consideringthat public Internet covers any application needs on the side of the user [30].

CN; and, in other networks, such as the AWMN, members occasion-ally share their Internet connections with other users through APs.

Networks built by people with technological background tendto elaborate more on the provision of non-professional services.Tools for communication such as chat, email servers, mailing lists,wikis, forums, data exchange, entertainment like broadcast radios,podcasts and streaming are common services found in most CNs(AWMN, Ninux, Freifunk, guifi.net). AWMN and Ninux users havealso access to VoIP and chats, guifi.net users to videoconferencing,AWMN and guifi.net users to local clouds and FFDN and Freifunkand AWMN users to collaborative writing tools. Apart fromthe basic services used in most CNs, there are also several CNspecific ones i.e., multi-player gaming, broadcasting, live streaming,e-learning, local search engines (Quicksearch, Wahoo, Woogle) inAWMN, web proxies, FTP or shared disk servers, XMPP instantmessaging servers, IRC servers, cloud services as the Cloudydistribution [60] in guifi.net, Internet cube, BitTorrent tracker,IndeCP or Internet service in FFDN, private VoIP service andweather monitoring in Sarantaporo.gr.

F. Lawful framework of operationAn operational framework of CNs (legal status, rights,

obligations) which is not well defined may impede the attractionof new participants. The level of support of CN initiatives by thestate or local administration has an impact on users’ decisionsto join or not the network [1]. When local authorities or anotherthird-party organization with clear legal status are involved, e.g.,by signing licenses, the user’s concerns are easier overcome andthe decision to participate looks far less risky. The response of mostCN initiatives to these reservations is to develop legal entities, andset forth licenses and agreements as legal documents specifyingthe terms and conditions of participation in the network.

1) Operation as legal entities: The majority of CNs havedeveloped legal entities to represent the network to third parties(Table III-B3). For example, Guifi.net created the guifi.netFoundation, AWMN the Association of AWMN, FFDN consistsof non-profit member organizations registered as telecom operators,Sarantaporo.gr operates as a non-profit civil partnership subjectto the Greek legal framework about NPOs, Freifunk has theForderverein freie Netzwerke e.V. as a reference NPO authority,TakNet is a social enterprise and B4RN a community benefit society.

2) Licenses and Agreements: Besides the legal status, CNsnormally make use of legal documents, such as Licenses andAgreements, to specify the frame of their members’ participationand their own interaction with third-party entities.

Guifi.net and FFDN utilize a Network Commons License (NCL)for establishing the rights and duties of subscribed participants.Moreover, guifi.net has developed collaboration agreements (TypeA, Type B, Type C) that define the terms of conditions of thirdparty collaboration within the network. Any private sector entitythat wants to perform economic activities and use a significantamount of resources of the network has to sign an Agreementwith the Foundation and participate in the compensation system(section V-A4). Freifunk uses the PicoPeering Agreement thatpromotes the free exchange of data within the network Ninuxparticipants comply with the Ninux manifesto, which is a variationof the PicoPeering Agreement.

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Mechanisms Volunteers Users Private sector service providers Public agenciesDirect reciprocity xIndirect reciprocity xPunishment of free-riders xCommunity currencies x xGame-theoretic x xFinancial compensation xLocal data storage infrastructure xSocial events and meetings x xNew member induction processes xWorkshops and seminars xOnline material for DIY fans xLocal applications and services xOperation as legal entities x x xLicenses and Agreements x x

TABLE V: Incentive mechanisms and relevance to the CN stakeholders.

G. Incentive mechanism classification

Several of the incentive mechanisms that are described in sectionsfrom V-A to V-F have never gone beyond the paper analysis stage.On the other hand, several others are indeed applied in existing CNs.The financial compensation system of guifi.net, the social events,meetings and workshops organized by many CNs, the adoptionof licences in Freifunk and guifi.net, as well as the introductionof a lawful operational framework serve, one way or another, asincentive mechanisms that motivate the participation of differenttypes of stakeholders in CN initiatives, as shown in Table V-D2.

Some of these incentive mechanisms apply almost invariably to allCNs. The lawful operational status, for example, is mandatory if theCN wants to attract critical masses of users, but also private sector en-tities and the support from public agencies. Equally common amongCNs is the care for social events and meetings that can strengthenthe links between their members and satisfy socio-cultural motivesof users. On the contrary, incentive mechanisms of economicalnature, such as the financial compensation scheme and the donationcertificates issued bu guifi.net for tax deduction purposes are morerelevant in CNs that support commercial operations over them.

For sure, it would be rather wise to match the incentivemechanisms with the different stakeholder types. Hence, volunteerswould be more responsive to incentive mechanisms that underlinepolitical and cultural causes; private sector service providers wouldrespond, maybe exclusively, to incentive mechanisms with economicimplications; and local authorities will be much more prone to getinvolved when they realize that public expenses can be saved orsome political strategic objective be served through this involvement.

By far, the majority of incentive mechanisms target CN users. Oneaspect that is not well understood is how the effectiveness of a mech-anism varies with different features of the community; namely, if wecould have a characterization of a community according to a fixedset of attributes (urban vs. rural, educational level, professional back-ground, dominant political preferences) that could predict whichincentive mechanism would best mobilize its members. An impor-tant parameter in this context is the size of the community. Char-acterizations along attributes is easier if the community is small19

and with roughly uniform interests and professional background. As

19But not too small. The CN will not be sustainable if there are not enough humanresources to pull from.

their size grows, such characterizations become harder and so doesany attempt to predict the suitability of incentive mechanisms.

VI. DISCUSSION AND CONCLUSIONS

The survey has examined the issue of sustainability in communitynetworks and the various aspects within political, socio-culturaland economic perspectives for CN participants. Special focus hasbeen given to the economic sustainability of CNs. Open accessnetwork infrastructure models were presented and compared totradition telecom business models while possible funding optionsfrom private and public entities and CN members were analyzed.Economic sustainability is a challenging issue which seems to bea necessary but not the only sufficient condition for approachinga sustainable operation of the CN. Socio-cultural and politicperspectives are needed as well.

Chosen CNs were studied with respect to actual and theoreticalmechanisms for enhancing sustainability by organizing and encour-aging member participation. Each CN is composed by four basictypes of entities (i.e., volunteers, private sector entities, users, publicagencies). These entities experience their own motives for joiningthe network and take part in mechanisms deployed to organize theircontributions. In order to match their political, socio-cultural andeconomic interests, corresponding mechanisms have to be in place.

It appears that sustainability cannot be reached following a set ofexhaustive rules and there are no clearcut answers for approachingit. However, checkpoints or indicative guidelines can be used toassess it. These can be summarized in the following evaluationform following the fieldwork in [30].

A. Economy1) Market and model of provision:• To which extent is the community network supported by

non-profit/community based network access and servicesprovision?

• To which extent does the community network rely on acommercial provider? What is the nature of this provider (e.g.for-profit vs. social enterprise, or local vs. non-local)?

• To which extent does the model of network provision ofthe community network face competition from commercialfor-profit telcos on the basis of quality of signal/provision,lower cost and/or better network maintenance?

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2) Resources:• To which extent does the community network manage to

survive economically, i.e. to afford the necessary hardwareand labour-power necessary for running the network?

• To which extent can the community network ensure that it hasenough resources, supporters, workers, volunteers, and users?

• To which extent does the community network rely on internalfunding sources?

• To which extent does the community network rely on externalfunding sources? How regular are they?

• Are there possibilities for the community network toobtain public or municipal funding or to co-operate withmunicipalities, public institutions or the state in providingaccess and services?

• To which extent does the community network rely on asingle individual or a small group of actors for providing thenecessary resources (time, skills, money)?

3) Network wealth for all:• To which extent does the community network provide

gratis/cheap/affordable network and Internet access for all?• If subscriptions are used, are they affordable?• To which extent are there different pricing schemes such as for

residential users, small enterprises, bigger firms, and publicinstitutions (e.g. schools)?

• How can the community avoid or lower the digital divide?• What technological skills are required of the average user to

benefit from the community network?4) Needs:• To which extent are the community needs served by the

community network?• To which extent are the needs of diverse individuals (e.g. by

gender, age, nationality) and groups in the community servedby the community network?

• To which extent are the needs of local businesses served bythe community network?

B. Politics

1) Participation/governance:• How is the community network governed? How does it decide

on which rules, standards, licences, etc. are adopted?• To what extent does the community network allow and

encourage the participation of community members ingovernance processes?

• To what extent are there in place mechanisms for conflictresolution and for proceedings in the case of the violation ofcommunity rules?

2) Data ownership and control:• To which extent does the community network enhance the

protection of privacy of user data?• To which extent does the community network provide oppor-

tunities for active user involvement in the management of theirdata? What are the skills required and how are they provided?

• To which extent and for how long are user data kept in serverscontrolled centrally (e.g. by the network administrators)? Howdo you guarantee that data storage is done in line with dataprotection regulation and is privacy-friendly?

C. Culture

1) Community spirit:• How closely knit is the community? To which extent are trust

and solidarity present and how are they manifested?• To which degree is the community network a geek public that

has an elitist, exclusionary culture or a community public thatis based on a culture of unity in diversity?

• To which extent does the community network providemechanisms for learning, education, training, communication,conversations, community engagement, strong democracy,participation, co-operation, and well-being? In what ways?

• To which degree is the community network able to foster aculture of togetherness and conviviality that brings togetherpeople? In what ways?

D. Future research directions

Having looked carefully into the broader issue of sustainability,our future work is going to focus in specific CNs and will seek topropose incentive mechanisms that can address the sustainabilitychallenge. This is going to be pursued through different directions.

One direction is on the effort to import elements from the guifi.netmodel such as the involvement of professionals in the network andthe provision of commercial services over it. More specifically, partof the work will be devoted to analyzing the incentive mechanismsthat guifi.net has put in place: the sustainability of its compensationsystem, which is the main tool for incentivizing the participation ofcommercial entities in the CN; and the exportability of this modelto the newer and promising Sarantaporo.gr CN.

A second, related direction, is through the launch of an opensource mobile application over the CN that realizes mobile crowd-sourcing and sharing economy practices. We will analyze incentives(i.e., game theoretic tools, reciprocity theories) that can be embeddedin the application to maximize its use, and through that, the use of theCN. Following the prototype of the application released in [20], wewill then design incentives to accommodate the agricultural servicesthat are of interest in this case, taking into account the particularitiesof the CN network such as the ownership of network nodes andnetwork connectivity alternatives that are available in the area.

VII. ACKNOWLEDGMENTS

The authors acknowledge the support of the EuropeanCommission through the Horizon 2020 project netCommons(Contract number 688768, duration 2016-2018).

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